<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        body {
            /* 语法 animation: 动画名字  时间  其他; */
            /*  infinite  循环播放 */
            animation: aa 1s infinite;
        }

        /* 制作动画 */
        @keyframes aa {
            0% {
               background-color: #f00;
            } 
            20% {
                background-color: #ff0;
            }
            40% {
                background-color: #000;
            }
            100% {
                background-color: #f0f;
            }
        }
    </style>
</head>
<body>

   
    
</body>
</html>